Early- and long-term outcomes in patients with cardiac implantable electronic devices undergoing radiation therapy
M Dyrbus, M Tajstra, A Blachut, J Machowicz, T Rutkowski, J Wydmanski, M Gasior, S BlamekAbstract
Background
The number of patients with cardiac implantable electronic devices (CIEDs) undergoing radiation therapy (RT) continues to rise. However, there is no real-world evidence on long-term outcomes post-RT, and current guidelines do not define optimal follow-up strategies. We aimed to evaluate long-term CIED function after RT.
Methods
We retrospectively analysed all patients with CIEDs treated with RT in a tertiary cardio-oncology centre. Device risk was estimated according to European Society of Cardiology cardio-oncology guidelines. Early follow-up included device interrogations before and after RT, while long-term follow-up incorporated outpatient records and structured patient contact. All-cause survival was obtained from administrative data.
Results
A total of 388 patients (408 RT courses; 29.0% pacing-dependent) were included. High-risk RT occurred in 36.8% of cases, with 1.7% exposed to beam energies >10 MV. Acute right atrial and right ventricular pacing threshold rises ≥1.0 V were observed in 1.2–1.3% of patients, and one transient device reset was noted. Over a median (Q1–Q3) follow-up of 1.81 (0.97–3.52) years, all-cause mortality was 45.1%, with no significant differences regarding pacing dependence or device type. Among 141 patients with detailed long-term follow-up, only minor, non-progressive threshold changes were observed, rarely exceeding 1.0 V. No premature battery depletion or RT-related lead extractions occurred.
Conclusions
RT was associated with a low risk of acute or long-term CIED dysfunction. Adherence to current cardio-oncology recommendations enables safe RT delivery in patients with CIEDs, even over long-term follow-up suggesting that the post-RT device management may be similar to that of patients not requiring RT.